There's a funny thing when people get new wings or if they haven't flown for a while.
The tow pilots refuse to go to the coast to fly new gear. "I want to have a few tows before I fly this thing on the coast".
The ridge soaring pilots say "Hell no, I'm not towing this thing until I've flown it at least a few times on the coast".

It's a long-standing tradition in HG, NEVER combine two unknowns. This means that, for example,
coastal pilots should not make first flights, towing, on a new glider, if towing is less familiar to them than coastal flying conditions.

This applies to every phase of HG, even as far as landing a new glider in a new LZ. Certainly, it can be done,
but given the choice, on a new glider, I'd want to land in a familiar LZ (in this case), until I had a good handle on the new gear.
In the instance above, the pilot would be combining three unknowns: new glider, unfamiliar towing, and an unfamiliar LZ.

It's good to hear that the pilots involved have shown the good sense to decline such a poor combination of unfamiliar factors.
Some may say that the practice of "only one unknown" is too cautious. I maintain that the sky will be there tomorrow, and
I applaud any of my HG friends who take new things, one step at a time.

If you think back a bit, you may know personally of instances where a mishap occurred because the pilot was distracted
by two unfamiliar aspects of equipment and/or location at one time. Air does not hear "wait-a-minute!"
The sky waits for nobody.